In steady state conditions, currents flow through damper windings, which create problems for losses, electro-magnetic stress, heat-evolution etc. One of the reasons for such current flows is that there are space subharmonic m.m.f.'s, which are generated when fractional slot windings are adopted for armature windings. In this paper, we describe a method of analysis on damper winding currents due to subharmonic m.m.f.'s by use of FEM. In general, the region for analyzing subharmonic m.m.f.'s is multi pole-pitches, while that for a fundamental or a harmonic m.m.f. is one pole-pitch. In this paper, we present a method for the analysis with the aid of the symmetrical co-ordinate method, in which the region for the subharmonic m.m.f. can become one pole-pitch. Numerical examples for the method are shown.